It is well known in the food packaging art to stuff synthetic or cellulosic, flexible tubular casings or to stuff flexible thermoplastic bags with various meat products. Casings and bags are collectively herein referred to as "flexible thermoplastic containers". These meat products are typically processed and introduced into the casings or bags in the form of an emulsion or comminuted form.
In automated processes, processed meat products are introduced into a casing which may be unshirred, but such meat products are typically introduced into a shirred casing. This is a casing which is shirred to a much shorter length than the actual length of the casing. As the automated process is operated, the shirred casing is fed typically over a sizing ring which unshirres the casing before stuffing with the meat product. Of course, the diameter of the sizing ring will be predetermined in accordance with the size of the intended casing which will be used for the particular packaging operation. Such a process and apparatus is discussed in copending U.S. Ser. No. 282,794 filed Dec. 9, 1988 to inventor Stanek, the disclosure of which is incorporated herein by reference.
Also stuffing is done into flexible thermoplastic bags. An apparatus for such processes is sold under the trade name Furakawa 8150 vacuum meat stuffing apparatus. The 8150 is described in U.S. Pat. No. 4,586,320, the disclosure of which is incorporated herein by reference.
It is also common practice to introduce liquid smoke, colorant, disinfectant or other similar additives to certain processed meat products such as sausage or luncheon meats to impart the desired flavor or color or bactericide to the food product. These additives are usually blended into the food product before the stuffing operation, or impregnated into the bag or casing material itself if the composition of the plastic permits impregnation of such additives.
This general practice requires an additional step prior to the stuffing operation. In the instance of pre-blending the colorant or liquid smoke into the food product, sometimes more additive is used than is really required. For example, if only the surface of the food product requires the colorant or liquid smoke, pre-blending uses excess additive which is blended throughout the food product.
Additionally, in the instance of some synthetic casings, liquid smoke and colorant are not easily added to the polymeric pellet feed when manufacturing the casing material itself, and if added are not readily retained by the casing material.
For these reasons, it is desirable to provide a method and apparatus for coating the interior of a flexible thermoplastic container for packaging a processed meat product, which does not require the pre-blending of the additive into the meat before the stuffing operation, or impregnation of the plastic material itself with the additive.